A recent post to this list described the inability of the bandpass filter FL101 to pass frequencies in the 70cm Amateur band. The schematic diagram in the UHF MSR2000 service manual shows the four helicals to be adjustable, but it seems that the adjustments are concealed. Inasmuch as this filter prevents many Hams from retuning their stations down to 70cm, I would like to ask anyone with a spare MSR2000 UHF bandpass filter to allow me to see if it can be retuned. My intention is to first sweep the filter on a network analyzer to see what its "stock" response looks like. Then, if the owner of the filter allows it, I would see what is needed to gain access to the internal adjustments, and if retuning to the 70cm band is possible. I shall endeavor to return the filter to its owner after this investigation, either tuned as it was originally or tuned to favor 70cm. As you might expect, this "science project" will form the basis of a how-to article in the RBTIP.
I don't have a UHF MSR2000 to experiment on, so I am hopeful that someone "out there" may have an idle UHF MSR2000 station that can serve as a source for the FL101 filter. 73, Eric Lemmon WB6FLY
